十一选五选号计算公式: kubernetes API服務器的安全防護

12.1.了解認證機制

陕西十一选五 www.eoxav.com   啟動API服務器時,通過命令行選項可以開啟認證插件。

12.1.1.用戶和組

了解用戶:

  分為兩種連接到api服務器的客戶端:

  1.真實的人

  2.pod,使用一種稱為ServiceAccount的機制

了解組:

  認證插件會連同用戶名,和用戶id返回組,組可以一次性給用戶服務多個權限,不用單次賦予,

  system:unauthenticated組:用于所有認證插件都不會認證客戶端身份的請求。

  system:authenticated組:會自動分配給一個成功通過認證的用戶。

  system:serviceaccount組:包含 所有在系統中的serviceaccount。

  system:serviceaccount:<namespace>組:包含了所有在特定命名空間中的serviceAccount。

 

12.1.2 ServiceAccount介紹

  每個pod中都包含/var/run/secrets/kubernetes.io/serviceaccount/token文件,如下圖所示,文件內容用于對身份進行驗證,token文件持有serviceaccount的認證token。

  

  應用程序使用token去連接api服務器時,認證插件會對serviceaccount進行身份認證,并將serviceaccount的用戶名傳回到api服務器內部。

       serviceaccount的用戶名格式如下:

  system:serviceaccount:<namespace>:<service account name>

  ServiceAccount是運行在pod中的應用程序,和api服務器身份認證的一中方式。

了解ServiceAccount資源

  ServiceAcount作用在單一命名空間,為每個命名空間創建默認的ServiceAccount。

       

  多個pod可以使用相同命名空間下的同一的ServiceAccount,

 ServiceAccount如何與授權文件綁定

   在pod的manifest文件中,可以指定賬戶名稱的方式,將一個serviceAccount賦值給一個pod,如果不指定,將使用該命名空間下默認的ServiceAccount.

   可以 將不同的ServiceAccount賦值給pod,讓pod訪問不同的資源。

 

12.1.3創建ServiceAccount

  為了集群的安全性,可以手動創建ServiceAccount,可以限制只有允許的pod訪問對應的資源。

        創建方法如下:

$ kubectl get sa
NAME      SECRETS   AGE
default   1         21h


$ kubectl create serviceaccount yaohong
serviceaccount/yaohong created


$ kubectl get sa
NAME      SECRETS   AGE
default   1         21h
yaohong   1         3s

  使用describe來查看ServiceAccount。

$ kubectl describe sa yaohong
Name:                yaohong
Namespace:           default
Labels:              <none>
Annotations:         <none>
Image pull secrets:  <none>
Mountable secrets:   yaohong-token-qhbxn   //如果強制使用可掛載秘鑰。那么使用這個serviceaccount的pod只能掛載這個秘鑰
Tokens:              yaohong-token-qhbxn
Events:              <none>

  查看該token,

$ kubectl describe secret yaohong-token-qhbxn
Name:         yaohong-token-qhbxn
Namespace:    default
Labels:       <none>
Annotations:  kubernetes.io/service-account.name: yaohong
              kubernetes.io/service-account.uid: a3d0d2fe-bb43-11e9-ac1e-005056870b4d

Type:  kubernetes.io/service-account-token

Data
====
ca.crt:     1342 bytes
namespace:  7 bytes
token:      eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJkZWZhdWx0Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZWNyZXQubmFtZSI6Inlhb2hvbmctdG9rZW4tcWhieG4iLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC5uYW1lIjoieWFvaG9uZyIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50LnVpZCI6ImEzZDBkMmZlLWJiNDMtMTFlOS1hYzFlLTAwNTA1Njg3MGI0ZCIsInN1YiI6InN5c3RlbTpzZXJ2aWNlYWNjb3VudDpkZWZhdWx0Onlhb2hvbmcifQ.BwmbZKoM95hTr39BuZhinRT_vHF-typH4anjkL0HQxdVZEt_eie5TjUECV9UbLRRYIqYamkSxmyYapV150AQh-PvdcLYPmwKQLJDe1-7VC4mO2IuVdMCI_BnZFQBJobRK9EdPdbZ9uxc9l0RL5I5WyWoIjiwbrQvtCUEIkjT_99_NngdrIr7QD9S5SxHurgE3HQbmzC6ItU911LjmxtSvBqS5NApJoJaztDv0cHKvlT67ZZbverJaStQdxr4yiRbpSycRNArHy-UZKbNQXuzaZczSjVouo5A5hzgSHEBBJkQpQ6Tb-Ko5XGjjCgV_b9uQvhmgdPAus8GdFTTFAbCBw

  

12.1.4將ServiceAccount分配給pod

  在pod中定義的spec.serviceAccountName字段上設置,此字段必須在pod創建時設置后續不能被修改。

  自定義pod的ServiceAccount的方法如下圖

      

 

12.2通過基于角色的權限控制加強集群安全

12.2.1.介紹RBAC授權插件

  RBAC授權插件將用戶角色作為決定用戶能否執行操作的關機因素。

12.2.2介紹RBAC授權資源

  RBAC授權規則通過四種資源來進行配置的,他們可以分為兩組:

    Role和ClusterRole,他們決定資源上可執行哪些動詞。

         RoleBinding和ClusterRoleBinding,他們將上述角色綁定到特定的用戶,組或者ServiceAccounts上。

  Role和RoleBinding是namespace級別資源

  ClusterRole和ClusterRoleBinding是集群級別資源

 

12.2.3使用Role和RoleBinding

   Role資源定義了哪些操作可以在哪些資源上執行,

創建Role

  service-reader.yml

apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
  namespace: kube-system
  name: service-reader
rules:
- apiGroups: [""]
  verbs: ["get", "list"]
  resources: ["services"]

  在kube-system中創建Role

#kubectl -n kube-system create -f service-reader.yml

  查看該namespace下的role

$ kubectl -n kube-system get role
NAME                                             AGE
extension-apiserver-authentication-reader        41h
kube-state-metrics-resizer                       41h
service-reader                                   2m17s
system::leader-locking-kube-controller-manager   41h
system::leader-locking-kube-scheduler            41h
system:controller:bootstrap-signer               41h
system:controller:cloud-provider                 41h
system:controller:token-cleaner                  41h

綁定角色到ServiceAccount

   將service-reader角色綁定到default ServiceAccount

$ kubectl  create rolebinding test --role=service-reader
rolebinding.rbac.authorization.k8s.io/test created

  

$ kubectl  get rolebinding test -o yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  creationTimestamp: 2019-08-11T03:40:51Z
  name: test
  namespace: default
  resourceVersion: "239323"
  selfLink: /apis/rbac.authorization.k8s.io/v1/namespaces/default/rolebindings/test
  uid: d0aff243-bbe9-11e9-ac1e-005056870b4d
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: service-reader

  

12.2.4使用ClusterRole和ClusterRoleBinding

 查看集群ClusterRole

# kubectl get clusterrole 
NAME                                                                   AGE
admin                                                                  42h
cluster-admin                                                          42h
edit                                                                   42h
flannel                                                                42h
kube-state-metrics                                                     42h
system:aggregate-to-admin                                              42h
...

創建ClusterRole

kubectl create clusterrole flannel --verb=get,list -n kube-system 

查看yaml文件

# kubectl get  clusterrole flannel -o yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"rbac.authorization.k8s.io/v1","kind":"ClusterRole","metadata":{"annotations":{},"name":"flannel"},"rules":[{"apiGroups":[""],"resources":["pods"],"verbs":["get"]},{"apiGroups":[""],"resources":["nodes"],"verbs":["list","watch"]},{"apiGroups":[""],"resources":["nodes/status"],"verbs":["patch"]}]}
  creationTimestamp: 2019-08-09T09:58:42Z
  name: flannel
  resourceVersion: "360"
  selfLink: /apis/rbac.authorization.k8s.io/v1/clusterroles/flannel
  uid: 45100f6f-ba8c-11e9-8f57-005056870608
rules:
- apiGroups:
  - ""
  resources:
  - pods
  verbs:
  - get
- apiGroups:
  - ""
  resources:
  - nodes
  verbs:
  - list
  - watch
- apiGroups:
  - ""
  resources:
  - nodes/status
  verbs:
  - patch

 

創建clusterRoleBinding

$ kubectl  create clusterrolebinding  cluster-tetst  --clusterrole=pv-reader  --serviceaccount=kuebsystem:yaohong 
clusterrolebinding.rbac.authorization.k8s.io/cluster-tetst created

  

 

12.2.5了解默認的ClusterRole和ClusterRoleBinding

如下所示使用kubectl get clusterroles和kubectl get clusterrolesbinding可以獲取k8s默認資源。

用edit ClusterRole允許對資源進行修改

用admin ClusterRole賦予一個命名空間全部的權限

$ kubectl get clusterroles
NAME                                                                   AGE
admin                                                                  44h
cluster-admin                                                          44h
edit                                                                   44h
flannel                                                                44h
kube-state-metrics                                                     44h
system:aggregate-to-admin                                              44h
system:aggregate-to-edit                                               44h
system:aggregate-to-view                                               44h
system:auth-delegator                                                  44h
system:aws-cloud-provider                                              44h
system:basic-user                                                      44h
system:certificates.k8s.io:certificatesigningrequests:nodeclient       44h
system:certificates.k8s.io:certificatesigningrequests:selfnodeclient   44h
system:controller:attachdetach-controller                              44h
system:controller:certificate-controller                               44h
system:controller:clusterrole-aggregation-controller                   44h
。。。

  

[email protected]:~$ kubectl get clusterrolebindings
NAME                                                   AGE
clust-tetst                                            17m
cluster-admin                                          44h
cluster-tetst                                          13m
flannel                                                44h
kube-state-metrics                                     44h
kubelet-bootstrap                                      44h
system:aws-cloud-provider                              44h
system:basic-user                                      44h
system:controller:attachdetach-controller              44h
system:controller:certificate-controller               44h
。。。

 

posted @ 2019-08-11 14:54 姚紅 閱讀(...) 評論(...) 編輯 收藏